/*
 * Copyright (c) 2010, 2018 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

package org.glassfish.jersey.message.internal;

import java.text.ParseException;

import org.glassfish.jersey.internal.LocalizationMessages;

import static org.glassfish.jersey.message.internal.GrammarUtil.COMMENT;
import static org.glassfish.jersey.message.internal.GrammarUtil.CONTROL;
import static org.glassfish.jersey.message.internal.GrammarUtil.QUOTED_STRING;
import static org.glassfish.jersey.message.internal.GrammarUtil.SEPARATOR;
import static org.glassfish.jersey.message.internal.GrammarUtil.TOKEN;
import static org.glassfish.jersey.message.internal.GrammarUtil.filterToken;
import static org.glassfish.jersey.message.internal.GrammarUtil.getType;
import static org.glassfish.jersey.message.internal.GrammarUtil.isSeparator;
import static org.glassfish.jersey.message.internal.GrammarUtil.isToken;
import static org.glassfish.jersey.message.internal.GrammarUtil.isWhiteSpace;

Concrete internal implementation of pull-based HTTP reader.
Author:Paul Sandoz, Martin Matula
/** * Concrete internal implementation of pull-based HTTP reader. * * @author Paul Sandoz * @author Martin Matula */
/* package */ final class HttpHeaderReaderImpl extends HttpHeaderReader { private final CharSequence header; private final boolean processComments; private final int length; private int index; private Event event; private CharSequence value; HttpHeaderReaderImpl(String header, boolean processComments) { this.header = (header == null) ? "" : header; this.processComments = processComments; this.index = 0; this.length = this.header.length(); } HttpHeaderReaderImpl(String header) { this(header, false); } @Override public boolean hasNext() { return skipWhiteSpace(); } @Override public boolean hasNextSeparator(char separator, boolean skipWhiteSpace) { if (skipWhiteSpace) { skipWhiteSpace(); } if (index >= length) { return false; } char c = header.charAt(index); return isSeparator(c) && c == separator; } @Override public String nextSeparatedString(char startSeparator, char endSeparator) throws ParseException { nextSeparator(startSeparator); final int start = index; for (; index < length; index++) { if (header.charAt(index) == endSeparator) { break; } } if (start == index) { // no token between separators throw new ParseException(LocalizationMessages.HTTP_HEADER_NO_CHARS_BETWEEN_SEPARATORS(startSeparator, endSeparator), index); } else if (index == length) { // no end separator throw new ParseException(LocalizationMessages.HTTP_HEADER_NO_END_SEPARATOR(endSeparator), index); } event = Event.Token; value = header.subSequence(start, index++); return value.toString(); } @Override public Event next() throws ParseException { return next(true); } @Override public Event next(boolean skipWhiteSpace) throws ParseException { return next(skipWhiteSpace, false); } @Override public Event next(boolean skipWhiteSpace, boolean preserveBackslash) throws ParseException { return event = process(getNextCharacter(skipWhiteSpace), preserveBackslash); } @Override public Event getEvent() { return event; } @Override public CharSequence getEventValue() { return value; } @Override public CharSequence getRemainder() { return (index < length) ? header.subSequence(index, header.length()) : null; } @Override public int getIndex() { return index; } private boolean skipWhiteSpace() { for (; index < length; index++) { if (!isWhiteSpace(header.charAt(index))) { return true; } } return false; } private char getNextCharacter(boolean skipWhiteSpace) throws ParseException { if (skipWhiteSpace) { skipWhiteSpace(); } if (index >= length) { throw new ParseException(LocalizationMessages.HTTP_HEADER_END_OF_HEADER(), index); } return header.charAt(index); } private Event process(char c, boolean preserveBackslash) throws ParseException { if (c > Byte.MAX_VALUE) { index++; return Event.Control; } switch (getType(c)) { case TOKEN: { final int start = index; for (index++; index < length; index++) { if (!isToken(header.charAt(index))) { break; } } value = header.subSequence(start, index); return Event.Token; } case QUOTED_STRING: processQuotedString(preserveBackslash); return Event.QuotedString; case COMMENT: if (!processComments) { throw new ParseException(LocalizationMessages.HTTP_HEADER_COMMENTS_NOT_ALLOWED(), index); } processComment(); return Event.Comment; case SEPARATOR: index++; value = String.valueOf(c); return Event.Separator; case CONTROL: index++; value = String.valueOf(c); return Event.Control; default: // White space throw new ParseException(LocalizationMessages.HTTP_HEADER_WHITESPACE_NOT_ALLOWED(), index); } } private void processComment() throws ParseException { boolean filter = false; int nesting; int start; for (start = ++index, nesting = 1; nesting > 0 && index < length; index++) { char c = header.charAt(index); if (c == '\\') { index++; filter = true; } else if (c == '\r') { filter = true; } else if (c == '(') { nesting++; } else if (c == ')') { nesting--; } } if (nesting != 0) { throw new ParseException(LocalizationMessages.HTTP_HEADER_UNBALANCED_COMMENTS(), index); } value = (filter) ? filterToken(header, start, index - 1) : header.subSequence(start, index - 1); } private void processQuotedString(boolean preserveBackslash) throws ParseException { boolean filter = false; for (int start = ++index; index < length; index++) { char c = this.header.charAt(index); if (!preserveBackslash && c == '\\') { index++; filter = true; } else if (c == '\r') { filter = true; } else if (c == '"') { value = (filter) ? filterToken(header, start, index, preserveBackslash) : header.subSequence(start, index); index++; return; } } throw new ParseException(LocalizationMessages.HTTP_HEADER_UNBALANCED_QUOTED(), index); } }